Roasting-furnace.



No. 814,238. PATENTBD MAR. 6, 1906.

T. F. SHERIDAN. ROASTING FURNACE.

APPLIUATIGN FIRE?) NOV, 20, 1905.

2 SKEETSSHEET 1.

PATBNTED MAR. 5, 1906.

T. P. SHERIDAN. ROA$TG FQRNACE.

APPLimTmx FILED NOV. 20, 1905 a sums-$55121 2 c" 6 j I 1? a1 a Q, I J ,1: v x; ,7 .3

THQMAS F. SHERIDAN, OF CHICAGO, ILLINOIS, ASSIGNOR TO ALLlS- UHALMERS COMPANY, OF MILWAUKEE,

TION OF NEIN JERSEY.

Vl lSCONSIN, A CORPORA- ROASTING-FURNACE.

Specification of Letters Patent.

Patented March 6, 1906.

Application filed November 20, 1905. Serial No, 288,321.

To all whom it may concern:

Be it known that I, THOMAS F. SHERIDAN, a citizen of the United States, residing in Chicage, inthe county of Cook and State of Illinois have invented certain new and useful Improvements in Roasting-Furnaces, of which the followinn is a specification.

My invention reilates to roasting-furnaces of the type in which the ore under treatment is stirred or agitated b r the action of hollow stirrin or rake arms w ich are sup lied with water or the purpose of keeping t ein relatively cool, and has for its object to rovide an improved means for cooling the ral e-arms and keeping them at a uniform temperature with the use of a minimum quantity of water, and consequently at a minimum expense.

The invention consists in the devices set forth in the accompanying specification and described in the claims.

In the drawings, Fi ure 1 is a sectional elevation of a roastingurnace containing any improvements; Fig. 2, an enlarged sectional detail showing one of the rake-arms F 3 a view similar to Fig. 2, showing a mo idea tion; and Fig. 4, a sectional plan View of the parts shown in Fig. 3.

In the drawings, a represents the shell of a well-known type of roasting-furnace. This furnace is rovlded with hearths b b if. An upright ho 0w shaft 0, carryin hollow rake arms d, communicat' with t e exterior of said shaft, is mounted in the furnace and has at its lower end a suitable ear f, whereby it may be rotated in the we] -known manner. Within this hollow shaft is a suppl -pipe 0'', connected by a pipe lcwith any suita 1e source of water-supply. Connected to this supplypipe and communicating therewith is a series of branch pipes e, which extend into the interior of each of the hollow rake-arms to the outer end thereof, where they are connected to a head 2 To this head are also connected return-pipes e, which extend from the head to the interior of the hollow shaft, where they are provided with a terminal opening. As shown in Fig. 1, the head is arranged vertically. Consequently the return-pipes are arran ed in a similar manner above and below t 1e branch pi e e. The upper returnpipes are upturne at their inner end, as shown, for a pur ose presently to be described. At its upper on 'thehollow shaft is provided withKdischarge-pipes g, discharging into a trough h, from which the water may be conveyed by an suitable means to its oint of discharge. he furnace, with its iearths, hollow shaft, and the supply pipe therein, forms no part of my invention, which concerns itself with the means for maintaining the rake-arms at a uniform comparatively low temperature.

In operation the ore is fed to the upper hearth, where it is subjected to the action of heat and stirred by the rotating rake-arms and discharged thereby through a central opening to the next lower hearth. A similar series of rakearnis is provided on this hearth, though I have not shown them, which discharge the ore throu h a mar inal opening to the third hearth. his is wel known, however, and needs no particular description. Water is supplied to the supplyipe tinnigh its connection is with a source 0 su )ply, and this water fills the interior of the hollow shaf t and the hollow arms when the furnace is in operation. Owing to the great heat which is maintained in these furnaces, the shaft and the rake-arms, with the water therein,w0uld soon become overheated, unless some means to prevent this is provided. Consequently I maintain a circulation of cold water in the supply-pipe and the branch and return pipes. The cold water fiowin through the supplypipe and the brane pipes is returned through the return-pipes to the terminal openings-of the returni es, which, as above stated, are within the li o low shaft. During its circulation the water in the pi es becomes heated. Conse uentlyitisathlg ertemperature at the disc argeoint than the incoming supply. It has t erefore a tendency to rise to t e discharge-pipesg,wbence it is conveyed away.

It will be observed that the cold water in the supply,branch, and return pipes does not come 1n contact with the water n the rakearmS that is, there is no mingling of hot and cold water in these arms, but the water in the arms is maintained at a uniform comparativelv low temperature by reason of its contact throughout the length oi the rake-arms with the cooled pipes.

In the former constructions of which I am aware the branch pipes in the rake-arms conveyed the cooled water from the supply-pipe slowly, since it is not displaced by any body to a point adjacent the outer end of the hollow arms, where the branch pipe is provided with a terminal opening. In such a construction it will be recognized that in order to maintain a circulation of cold water in the hollow rake-arms it is necessary to supply a sufficient amount of cold water to displace the body of heated water therein. It will also be seen that when the cold water is supplied to the outer end of the hollow rakearms such rake-arms will be cooled to a greater degree at this pointthat is, they will not be cooled to a uniform extent. By carrying the cold water through a series of ipes out of contact with the water in the hollow arms I am enabled to cool the water in the arms to a uniform extent. It is not necessary in my construction to provide a sufficient amount of cold water to displace the heated water in the hollow arms. All that is necessary is to supply a sufficient 3 quantity of cold water to maintain the body 1 of water in the hollow arms at the desired temperature. It will thus be seen that the water in the hollow arms will be changed of incoming water, but only by the circula tion caused by its tendency to rise when heated. I am thus enabled to keep the rakej arms at the desired temperature wlth a mini 5 mum amount of cold water at low temperature and at a minimum expense. I

In Figs. 3 and 4 I have shown the returnpipes arranged horizontally instead of vertically, which may be readily done by arranging the head e in a horizontal osition, as will be understood. The ends of the return-pipes within the hollow shaft are upturned, as before stated. This is to assist the water in its circulation. The water being heated at this point to a somewhat greater degree than at other points in its course its tendency is to rise to the point of discharge. The water, therefore, is discharged from the upturned ends in the direction which it would naturally take.

1. In a roasting-furnace, a hollow upright shaft, hollow horizontallyarranged rakearms connected thereto and communicating with the interior of the shaft, and means for fillin the shaft and arms with water and for circu ating a cooling medium through the arms out ofcontact with the water therein.

2. In a roasting-furnace, a hollow upri ht shaft, horizontally-arranged hollow ra earms attached thereto and communicating with the interior thereof, a suppl -pipe in the shaft, branch pipes in the ho low arms communicating with the su ply-pipe, said branch pi es having terminaFopenmgs within the hol ow shaft.

3. In a roasting-furnace, a hollow shaft, hollow rake-arms connected thereto and communicating therewith, a supply-pipe in such shaft, pipes connected with the sup lypipie extending to the outer end of the ho ow ra e-arms and provided with return branches having terminal openings within the hollow shaft.

THOMAS F. SHERIDAN. Witnesses:

ANNIE C. OOURTENAY, JENNIE MACEDWARD. 

